Ladder and safety-lock



A. DI SALVATORE. LADDER AND SAFETY LOCK.

APPLICATION FILED APR. 19, I920.

1,352,055. Patented Sept. 7, 1920.

/Lg T I.

amntoz AfDl SALVATORE.

LADDER AND SAFETY LOCK.

APPLICATION FILED APR. 19. 1920.

Patented Sept. 7, 1920.

2 SHEETS-SHEET 2.

UNITED STATES PATENT OFFICE.

ANTHONY DI SALVATORE, OF SGOTIA, NEW" YORK.

LADDER AND SAFETY-LOCK.

To all whom it may concern Be it known that I, ANTHONY Dr SALVA- rorn, a citizen of the United States, residing at Scotia, in the county of Schenectady and State of New York, have invented certain new and useful Improvements in Ladders and Safety-Locks; and I do declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to an improved ladder such as is commonly used in stores for reaching articles placed upon high shelves. It is customary to provide a ladder which is slidably mounted upon upper andlower tracks so that the ladder may be moved longitudinally of the shelves to the point where it is to be used. It has been found exceedingly dangerous to provide a ladder of this type without a lock which will prevent moving of the ladder while in use as it often happens that when one person is standing upon the ladder another who wishes to use the ladder will move the ladder thus causing the person standing upon the ladder to fall. Various locks have been provided for looking a ladder of this type but looks now in use are all so constructed that they may be easily released from the flooring, and if the person who wishes to use the ladder does not look to see if it is already in use the lock often is released and the ladder removed, thus causing the person standing upon the ladder to fall.

In order to overcome the objections noted above the lock which forms the subject matter of this invention has been provided, the lock being so constructed that it may be securely locked by the person using the ladder thus preventing another who wishes to use the ladder from releasing the look at the first attempt. If the lock does not release at the first attempt the person who desires to use the ladder will naturally look up to see what is wrong with the lock and will then observe that the ladder is already 1n use.

Another object ofthe invention is to so construct this look that the person using-the ladder may release the lock in case the user desires to move the ladder without getting off of it and to further so construct the lock that it may be moved to an operative position or inoperative position from a number of positions upon the ladder.

Specification of Letters Patent.

Patented Sept. 7, 1920.

Application filed April 19, 1920. Serial No. 375,044.;

Another object of the invention is to so construct the lock and actuating means that it may be released from the floor in case a user of the ladder forgets to release the look when finished using the ladder.

Another object of the invention is to provide a lock which is so constructed that it may be applied to ladders already installed thus making it unnecessary to provide a special construction of ladder.

This invention is illustrated in the accompanying drawings wherein Figure 1 is a perspective View of the upper end portion of a ladder having the im- PTOIYGCl locking structure connected theres wit Fig. 2 is a view showing the ladder in elevation and locking at the under or rear side of the ladder.

Fig. 3 is a fragmentary view in elevation with the locking device in an inoperative position.

This lock is used in connection with a lad I der indicated in general by the numeral 10 and provided at its upper end with a crosshead 11 carrying the truck or carriage 12 which will be provided with the usual wheels 13 for engaging the upper track 14' tween the upper ends of the side rails of the ladder and will be engaged by a gripping jaw 16 whichis pivotally connected with a supporting bracket 17 secured to the upper step of the ladder. This jaw is provided with a lever extension 18 which carries the usual weight 19 for swinging the jaw up wardly and causing the cable 15 to be tightly gripped between the jaw 16 and the overhanging end portion or stationary jaw 20 of the bracket 17. A line 21 is connected with the jaw and extends downwardly along the under side of the ladder and has its lower end connected with a ring or eye 22 secured to one of the lower steps of the ladder. This is a conventional type of grip for engaging the cable 15 and locking the ladder and as stated above it often happens that a person who desires to use the ladder will grasp the line-21 'anddraw it downwardly thus releasing the ladder without looking up to see if the ladder is in use; This places the person using the ladder in danger and. it is to overcome the objection noted that the lock that will now be described has been provided.

A. .line 23 ,is passed through conductor tubes 24 whi eli are secured to the underlace of one of the side rails and has. its upper end extending fromthe upper end of the upper tube 24l'and' provided with a ringor other similar ldev ice"25 which will prevent this line fromslipping intothe upper tube.

Thel'owerzend ofthis line extends into a tubular. housing 26 and will be provided with a similar ring. torpreventing the line from being. drawnup into the lower tube 24. In'order' to permit access to the lower end of this .line when necessary the housing 26,,h-a's been; provided with a side opening which wnrmrmn be closed by the door 27. Side lines 28 extend from the line 2-3 between theconductor tubes-2et and, these side..lines 28 f are passed through shorter. tubes 29 which are secured to the steps of the..,.ladder and terminate a short distance fromthetongues or arms-3U which extendw from the brackets 31 secured to the steps.

These lineSPQ-B are. connected. with the line 21 andli't will ,thus bc-seen that when the line28 is drawn-upon .fromits upper or lower end the lines 28- will be drawn transversely of the-ladder andtheline 21 will be moved thus drawing; the abutment balls 32 from a position above the arms 30 to a point .beyondthe tree ends of the arms t hen in use-.the-tubes 29' and; the brackets. 3,1 will the secured to certain of the lad-- der steps and preferably at about a seven or eight.steps apart. The-tubes 24; will then be put. in placewith their adjacent endsterminating; in spacedtrelationi above and be-. low the steps ,c-arryn g the z brackets; "31 and tubes-29 and-.lthe; housing 26 vwill be connected with the ladder to ielose the lower be placed upon the line 21 and secured at the, proper, points bythe set screws-33 so that these ballswillbe positioned to engage the upper edgesof' the arms 80 and the rear-- dgQlQOIillOllS: of the steps and: prevent down-- wardlmouement of the .line21 when the lineis the positionkshown in Figs. 1 and; 2. Th'ereforewhen a person 1s using the ladder theymayclimbto the desired point and may then. swing. the, line 21 to position the abut ment balls-as shown in Figs.; 1 and '2 and;

may then passwbetween. the armsv30 and tubes 29.. The line 21 may then be drawn downwardly to swing thejraw 16 out of-en gagcment with the e-able 15. After the lad-- der has been'moved to the desired position the line 21 will be released and the weight 19 will cause the lock to return to the opera-- tive vposition. If V a person desires to use: the ladder the line 21 will be grasped: and pulled downwardly andaif the ladder is not in use-the abutment balls willpass-between the arms SOand tubes-29 and permit the look to bereleased. If however, theladder is in use and the line swunghtothe position shown in Fig.2 the linewvillbe held against downward movementand when theline does not-move to release the. lockthe pei'sondesiring tousethel-adder willlook upto see what has prevented the lock from releasing. The person-usingthe ladder will then benotioedand the second partywill wait; untiltthe person. using the'ladder has. finish-ed; if the previoususer: has left the: ladder without releasing; the locking: device, it'is simplyuiecessary to open the'door 27 and the ring at thelower end-oi the :line 23 can. then'be: grasped and-.the l'inezpulled downwardly; to- .drawthe lines 28.0utwardly; andthus release theiloclnplt avi-ll'thus be=105 een that there hasrbeen provided a device:- by means of which 1 the line 21 may-beheld 5 against movement,- to release-the looking; jaw

16 and thus danger ofinjury toqpersons using theilad-der' prevented; a

What: is claimed is 1. A slidably mountedladderu-a lock for releasably" holding the ladder; against .sli'd-- ablewmovement, a l-ine connectedrwiththew lock moving the lock to anv-inoperative 1908111011,, anabutment element carried by .the-ladder,- -an abutmentielementzcarri-ed by the linle, for-engagingflhe; abutment elasments oftheladderfto retain the line against downward mo.vement,- and means acarriedby 2 0 the ladder; and; eonnectedto"themline for drawing the line to one side and permitting the abutment;carried-therebyto passthe line against downward movement, and means carried by the ladder and engaging the line for drawing the line to one side to position the abutments thereof out of engagement with the abutment brackets and permit movement of the line to release said lock.

3. A traveling ladder, a lock for the ladder, a line for moving the lock to a releasing position, abutment brackets carried by the ladder, abutment balls carried by the line for engaging the brackets, an actuating line slidably connected with the ladder and extending longitudinally thereof, and side lines extending from the actuating line and connected with the first mentioned line to draw the first mentioned line to one side when the actuating line is drawn upon and position the balls out of engagement with the brackets.

4. A traveling ladder, a lock for the same, a line connected with the lock for releasing the same, brackets connected with certain of the steps of said ladder and having abutment arms extending in spaced relation to the steps, abutment balls carried by the line for engaging the arms and holding the line against downward movement when the line is positioned to extend between the arms and the ladder steps, conductor tubes connected with one of the side rails of the ladder and terminating in spaced relation above and below the steps carrying the brackets, conductor tubes connected with the steps carrying the brackets, and side lines connected with the actuating line between the tubes of the side rail and extending through the tubes of the steps and connected with the first mentioned line.

5. The combination with a traveling ladder, a lock for the ladder, and a line connected with the lock for moving the lock to an inoperative position, of conductor tubes connected with one of the side rails of the ladder and having their adjacent ends terminating in spaced relation, a housing inclosing the lower end of the lower tube and provided with a normally closed inlet opening, an actuating line extending through the tubes with its lower end extending into the housing and its upper end extending in the upper end of the upper tube, an abutment carried by one of the steps of the ladder, an abutment carried by the first mentioned line for engaging the abutment of the ladder step, and a side line connected with the actuating line between the tubes and connected with the first mentioned line adjacent the abutment thereof to draw the first mentioned line to one side and position the abutment thereof out of engagement with the ladder abutment.

6. The combination with a traveling ladder, a lock for releasably holding the ladder against sliding movement and a line for moving the lock to an inoperative position, of an abutment carried by the ladder, an abutment carried by the line for engaging the ladder abutment to hold the line against movement to release the lock, and means connected with the first mentioned line for drawing the first mentioned line to position the abutment thereof out of engagement with the ladder abutment and permit movement of the first mentioned line to release the lock.

7. A traveling ladder, a lock for the same, an actuating line for the lock, means holding the line against movement to release the look when the line is in its normal position, and means for moving the line out of its normal position for movement to release the lock.

In testimony whereof I have hereunto set my hand.

ANTHONY DI SALVATORE. 

